Balanced slide-valve



Patented Dec. 13,1881.

A. KENDALL.

BALANGBD SLIDE VALVE.

(No Model.)

Ilma/afar.

UNITED STATES PATENT OFFICE.

ADONIRAM KENDALL, OF ERIE, PENNSYLVANIA.

BALANCED SLI DE-VALVE.

SPECIFICATION forming part of Letters Patent No. 250,925, dated December 13, 1881. Application filed May 2,1881. (No model.)

To all whom it may concern Beit known that I, ADONIRAM KENDALL, a citizen of the United States, a resident of Erie, Erie county, Pennsylvania, havein vented new and useful Improvements i n Balanced Slide-Valves for Engines and I do hereby declare that the following is a full, clear, and exact description thereof', reference being had to the accompanying drawings and the letters or figures of reference marked thereon.

My invention relates to steam -valves for steam-engines. The particular class of said valves to which myinvention most appertains is what are known as balanced slide-valves.

My invention consists in such improvements in the construction and operation ofthe same as are hereinafter specifically described and pointed out.

My device is illustrated in the accompanying drawings as follows:

Figure l is a perspective view with parts broken away, showing parts in vertical section. Fig. 2 is a vertical transverse section on the line y y in Fig. 1. Fig. 3 is a like view, being a longitudinal Asection on the line :c iu Fig. l. Fig. 4 is a similar view to Fig. 3 of a modified form.

A A is the steam-chest; B, the supply-pipe; C, the exhaust-passage; D, the exhaust-valve; E, the cut-off valve, which, together with the valve D, forms the whole valve. In Fig. 4 a single valveis shown, in place ota valve formed of two parts. p

The steam-passages are as follows: From the supply-passage B the steam enters the middle of the valve D, (marked 1),) tllence through an opening, b', thence through a passage, b, in the valve E, thence through a passage, p, in the cylinder, and out of the port P into the cylinder. In exhausting the steamv passes through the ports P and p in to the valve D and out through the passage C. The valve D is moved by the rod L, which connects with a ixed eccentric. The valve E is moved by a movable or variable eccentric. I do not claim bisecting the valve, nor the arrangementjust named for moving the segments.

In Fig. 4 a single valveis shown, with passages and ports substantially1 the same as those above described. With valve passages, as shown in each case, no steam would enter the steam-chest, and hence pressure upon the back of the valve does not occur. There should, however, be enough steam back of the valve to keep it seated. This I supply as follows Openings I and Jare made through the valves, (see Figs. l and 2,) one of which, I, connects with the supply and the other, J, with the exhaust through holes in the valve-seat. The passage into the exhaust is regulated in size by a stop-screw, j. When the valves reach the position shown in the drawings-which they do twice each revolution of the crank-steam will pass from the supply'into the chamber back of the valve, and will also exhaust into the exhaust passage; but sufficient will remain in the chamber to hold the valve upon its seat.

What I claim as new isl. In the balanced slide-valve of a steamengine, the openings I and J through said valve, in combination with corresponding holes through the valve-seat, one of which enters the supply-passage and the other the exhaustpassage, whereby as the valve moves steam passes into and exhausts from the chamber back of the valve, as set forth.

2. In the balance slide-valve of a steam-engine, the openings I and J, with gage-stopsj in the opening J, substantially as and for the purposes set forth.

3. In a steam-engine, a slide-valve consisting of two parts, D and E, with passages c c b b b therein, in combination with passages I B Cpp in the body of the cylinder, substantially as and for the purposes set forth.

4. In a steam-engine, a slide-valve having two live-steam passages therein, extending respectively from near the middle in opposite directions and opening near the ends of the valve, and serve alternately as steam-passages to the cylinder ports, in combination with openings through said valve near the middle, to convey steam to and exhaust it from the chamber back of the valve, substantially as shown.

In testimony that I claim the foregoing I have hereunto set my hand this 9th day of April, 1881.

ADONIRAM KENDALL.

Witnesses:

JN0. K. HALLocnz,V J. H. STONEMETZ. 

